To the court of King Bithynia Prussia two of his sons arrive. Nycomed, the son of the first marriage, left the army, at the head of which he won numerous victories, laying at the feet of his father not one kingdom; his deceit was enticed into the capital by his stepmother, Arsinoe. The son of Prussia and Arsinoe, Attalus, returned to his homeland from Rome, where he had been a hostage since the age of four; the efforts of the Roman ambassador Flaminius Attalus were released to their parents for the fact that they agreed to extradite the worst enemy of the enemy to her, Hannibal, but the Romans did not enjoy the spectacle of the captive Carthaginian, for he preferred to take poison.
The queen, as is often the case with the second wives, completely subordinated her influence to the aged Prussia. It was at her will that Prusias, for the sake of Rome, deprived her protection of Hannibal, now she was weaving intrigues, wanting to make his son Attalus the heir to the throne instead of Nycomed, and also upset the marriage of the stepson with the Armenian queen Laodike.
Arsinoe is supported by Flaminius in her intrigues, for it is in the interests of Rome, on the one hand, to elevate Attal to the Bithynian throne of Attal, who received the Roman upbringing and Roman citizenship, and not the proud and independent, famous in the campaigns of Nycomed, and on the other, to prevent the strengthening of Bithynia at the expense of the dynastic
Until now, half-brothers were not acquainted with each other and for the first time meet in the presence of Laodike, in which they are both in love, but only Nycomed she reciprocates. This first meeting almost ended in a quarrel. Arsinoe friction between brothers is only on hand, because according to her plans one of them must be broken, the other, on the contrary, is exalted. The Tsarina is sure that with the help of the Romans Attal will easily take the father’s throne; that before marrying Laodice, it is more difficult, but nevertheless she sees a way to ruin Nycomed and force the Armenian queen to enter into an unwanted marriage.
King Prussia has recently been alarmed by the unprecedented rise of Nycomed: the victor of Pontus, Cappadocia and the country of Galatians enjoys power, glory and popular love greater than those that ever came to his father’s share. As Prussia tells the lessons of history, such heroes are often bored with the title of subject, and then, wishing the king’s dignity, they do not spare the princes. The chief of the bodyguards, Prussia, Arasp, convinces the king that his fears would have been justified, when it was about someone else, the honor and nobility of Nycomed are not subject to doubt. Araspas’s arguments do not completely dispel Prussia’s anxieties, and he decides to try, acting with extraordinarily careful caution, to send Nycomed to honorable exile.
When Nycomed is to his father, in order to tell of his victories, Prussia meets him very coldly and reproaches him for having left his entrusted army. To the respectful request of Nycomed to allow him to accompany the outgoing Laodike, the king responds with a refusal.
The conversation between father and son is interrupted by the appearance of the Roman ambassador Flaminius, who on behalf of the republic demands that Prussia appoint Attal as his heir. To give an answer to Ambassador Prusias tells Nycomed that he resolutely rejects his demand, exposing Rome’s plans to weaken Bithynia, who, with such a king as Attal, will lose all its greatness with the newly acquired lands.
To agree among themselves Flaminia and Nycomed, besides the difference of aspirations, the enmity that separates them also hinders: Flaminius’s father, at the battle of Lake Trasimeno, fell by the hand of Hannibal, the teacher of Nycomed, highly respected by them. Flamingius nevertheless makes a concession: Nycomed will rule Bithynia, but with the proviso that Attal will marry Laodike and ascend to the Armenian throne. Nycomed also this time answers Flaminia with a resolute refusal.
Prussia is not alien to nobility, and although Laodike is in his power, he does not consider it possible to repair violence against a royal person. Therefore, as soon as Rome is pleased with the marriage of Attal and Laodice, let Flaminius go to the Armenian princess and on behalf of the republic offer her the son of Arsinoe.
Flaminia’s plan was not destined to come true – on the way to the gallery, Nycomed escaped with the help of an unknown friend. The prince goes out to the crowd, and the rebellious people immediately calmed down. In the consciousness of his own power he appears before terrified household members and the Roman ambassador, but he does not even think of revenge: everyone who wanted to harm him can be justified: his stepmother was guided by a blind love for his son, father – passion for Arsinoe, Flaminia – countries. Nycomed is forgiving all, but for Attala he promises to conquer any of the neighboring kingdoms that Arsinoe will like.
Nycomed touched the stepmother’s heart, and she sincerely promises to love him from now on, like her own son. Immediately, by the way, it turns out that the friend who helped Nycomed run, was Attal.
Prussia has no choice but to order the sacrifices in order to ask the gods to give Bithynia a lasting peace with Rome.